Computer.



PATENTED JUNE 13, 1905.

C. CAMPBELL, JR.

COMPUTER.

APPLICATION FILED JAN.26.1905.

2 SHEBTSSHEET 1,

Manfit.

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PATENTED JUNE 13, 1905.

C. CAMPBELL, JR.

COMPUTER.

APPLIOATION TILED JAN. 20. 1905.

2 SHEETS-SHEET 2,

Iw/anfif: 32:37 CamyZaZZc/z'f UNITED STATES Patented June 13, 1905.

COLIN CAMPBELL, JR, OF UNION, NE\V JERSEY.

COMPUTER.

SPECIFICATION forming part of Letters Patent No. 792,398, dated June 13, 1905.

Application filed January 26, 1905. Serial No. 242,778.

T wit/11m it may concern:

Be it known that 1, COLIN CAMPBELL, Jr., a citizen of the United States, residing in Union, in the county of Hudson and State of New Jersey, have invented certain new and useful Improvements in Computers, of which the following is a specification.

This invention has reference to means whereby interest, mileage, wages, &e., may be eli iciently and mechanically computed with reference to a given rate without mental additions or multiplications.

This invention may be embodied in any suitable mechanism best calculated to accomplish the results desired, and such embodiment of such invention as is illustrated on the accompanying sheets of drawings shows a device whereby mileage at given rates may be readily computed.

Figure 1 on said drawings illustrates an elevational view of a computing device. Fig. 2 illustrates, perspectively, two dissembled drums or cylinders of said device. Fig. 3 illustrates the sight-board carried by the casing and \vherethrough may be noticed various calculations of a given number of miles with reference to a variety of rates, and Fig. t shows a similar view exhibiting a diiferent set of calculations.

Similar characters of reference indicate similar parts in the ligures.

\Vithin a casing 5, mounted on a suitable base 6, are two drums or cylinders 7 and 8, respectively, which are adapted to telescope and revolve one within the other. The drum 7 is rotatably mounted upon a spindle 9, to which is secured means 10 for manipulating the spindle and drum, such means in the present instance embodying a milled head. The drum 8 is also provided with a hollow spindle 11, which is telescoped upon the spindle 9, and this drum is provided with a milled head by which the drum 8 may be rotated. and which head extends from the casing on a side opposite that from which the head 10 projects. The outer drum or cylinder 7 in the present instance is provided with a plurality of open ings 13, preferably disposed in rows or columns 14, 15, 16, 17. and 18. Above each opening in the rows 15, v16, 17, and 18 are placed numerals, which in the present instance are intended to indicate dollars and cents. Laterally of the openings in the row 1 1 on this drum are figures which are representative of the number of miles to be calculated from. While this latter set of numbers for convenience of illustration are shown as smaller denominations, in practice this column of numerals will preferably range from one thousand to any higher desirable numeral. On the surface of the drum 8 are recorded five rows of numerals, which rows are designated by 19, 20, 21, 22, and 23, and these rows correspond in location with the rows let, 15, 16, 17, and 18 of openings in the drum 7.

The row 19 of numerals on the inner drum 8 are representative in the present instance of miles and are visible through the openings in the drum '7 and in the row 14. The movability ot' the two drums relatively to each other permits the so-called mileage-numerals to be increased or decreased at will.

The numbers of the rows 20, 21, 22, and 23 are visible through the openings in the rows 15, 16, 17, and 18, and these numbers are adapted to be located beneath the numerals over the openings aforementioned, and thetotal of the numerals presented through the opening and the numeral above the opening give the resultant sought to be obtained. In other words, as a means of quick and ready calculation only two sets of numerals need be considered in mental calculation.

The object of providing a plurality of rows of numerals is to make a ready reference for a plurality of rates indicated, for example, by .036, .0365, .O il, and .04L2 in Figs. 3 and 4: on Sheet 2 of the drawings, it being obvious, of course, that according to the number of rates the number of rows will be correspondingly increased.

The rate indications are in the present instance carried upon a sight-board 24:, which is suitably secured to the casing and which is provided with openings 25, through which all the aforesaid numerals intermittently appear.

The board is also furnished with two extensions 26 and 27, each of which is provided with an opening 28 and 29, respectively, for ascertaining in advance the numeral desired to appear in the opening 30.

The structure herein delineated, it will be observed, need not within the purview of this invention be actually adhered to, for in the carryingforward of the principle outlined by this invention any suitable structure best calculated to give best results may be readily adopted.

As an example of the operation of this device let it be assumed that the numeral on the drum 7 and in the row 14 appears through the opening to represent 2,000. The numerals of the rows 15, 16, 17, and 18 will then be 72.00, 73.00, 82.00, and 84.00, which will be indicative of the t0- tals of two thousand miles at .036, .0365, .041, and .042 per mile. Let it then be assumed that the numerals of the row 19 on the inner drum 8 shall appear alongside of the numeral 20 and, say, this numeral shall be also 20, showing a total of 2020 miles. Then the totals for the different rates shown will be 72.72 for the.036 rate, 73.73 for the .0365 rate, 82.82 for the .041 rate, and 84.84 for the .042 rate, it being understood that the figures 72, 73, 82, and 84 are carried in the rows or columns 20, 21, 22, and 23 on the drum 8.

It may be here remarked that the relative movement of the two cylinders makes it possible to gain a wide variety of results with a construction of this character.

In referring to the term miles herein it is intended only as a designating term, and the term may be readily substituted byany other term or character.

Having thus described this invention, I claim A computing device comprising two uprights having opposite apertures, a drum having an axial shaft projecting from one end and through one of said apertured uprights, a head on the outer end of such shaft for turning the drum, a second drum registering with said drum and having an axial tube surrounding the shaft of the other drum, the second y drum having its axial member projecting through the other apertured upright, and a head on such projection for turning the second drum, the outer drum being provided with slots and rows of numerals, and the inner drum being provided with rows of numerals arranged to register with such slots in the outer drum, and a member carried by the uprights adjacent the outer drum and having slots to which said numerals can be brought to register.

Signed at Nos. 9 to 15 Murray street, in the city, county, and State of New York, this 23d 'day of January, 1905.

COLIN CAMPBELL, JR. Witnesses:

FRED W. BARNACLO, JOHN O. SEIFERT. 

